OpenSystemsDevelopment / qpdf

Add methods isNameAndEquals, isDictionaryOfType, isStreamOfType

Too bad about git annotate but it was pretty crazy to have all those
test cases together like that.

* Make it a runtime error, not a logic error
* Include additional information
* Capture it properly in checkLinearization

* Handle error conditions that occur when using the object handle
  interfaces. In the past, some exceptions were not correctly
  converted to errors or warnings.
* Add more detailed information to qpdf-c.h
* Make it possible to work more explicitly with uninitialized objects

Thanks for the nudge from m-holger!

Don't assume endobj is at the beginning of the line. This means we are
looking at tokens for every line, but the odds of n n obj appearing in
the middle of the object are likely much lower than endobj not being
at the beginning of the line or missing entirely. This will probably
have a negative impact on recovery time for very large files.
Hopefully it will be worth it.

When making resources indirect in from_dr, the code was using the
wrong owning QPDF, forgetting that from_dr had already been copied
using CopyForeignObject.

When adding a QPDFObjectHandle to an array or dictionary, if possible,
check if the new object belongs to the same QPDF. This makes it much
easier to find incorrect code than waiting for the situation to be
detected when the file is written.

The /Subtype entry that specifies the mime type of an embedded file is
inside the embedded file stream dictionary directly, not it in the
parameter dictionary.

See Table 45 and 46 in the PDF 1.7 specification:
https://www.adobe.com/content/dam/acom/en/devnet/pdf/pdfs/PDF32000_2008.pdf#page=112

Also handle direct annotation, though this is much less likely.

When copying a page from the original file to the output in --pages,
don't alter the fields or annotations for the first copy of each page.

Also improve behavior around direct vs. indirect resources.

Converted ResourceFinder to ParserCallbacks so we can better detect
the name that precedes various operators and use the operators to sort
the names into resource types. This enables us to be smarter about
detecting unreferenced resources in pages and also sets the stage for
reconciling differences in /DR across documents.

If not found in the field hierarchy, /Q and /DA are supposed to be
looked up in the document-level form dictionary. /DR is supposed to
only come from the document dictionary.

This results in a performance penalty of 1% to 2% when replaceObject
and swapObjects are never called and a somewhat larger penalty if they
are called, but it's worth it to avoid very confusing behavior as
discussed in depth in qpdf#507.